An ignition system in a combustion chamber of an engine includes an igniter for igniting a combustible air-fuel mixture in the chamber. The igniter may use a non-thermal corona discharge generated by the application of high voltage to an electrode such that current flows from sharp corners or projecting points of the electrode to ionize the air in the chamber to create a region of plasma around the electrode providing a plasma discharge streamer to ignite the air-fuel mixture. The plasma discharge streamer is restricted to a small area. Plasma (corona) discharge exhibits a propensity for arcing, such that voltage and/or duration of the ignition event must be closely controlled to minimize or prevent arcing.
Barrier discharge igniters do not exhibit arcing due to a non-conducting coating which prevents transition of the plasma discharge into an arc. The ignition provided by a barrier discharge igniter is provided by the electrical discharge between two electrodes separated by a dielectric barrier such that the ignition is confined to a small volume defined by the gap between the electrodes. Such a system is described by t. Shiraishi et al. in SAE Technical Paper 2011-01-0660 entitled Fundamental Analysis of Combustion Initiation Characteristics of Low Temperature Plasma Ignition for Internal Combustion Gasoline Engine, published Apr. 12, 2011, doi: 10.4271/2011-01-0660.